Any current processor keeps up with the GTX 1070, even at 1080p, so choose on price. The Ryzen 5 5600 or the Core i5-12400 keeps up as well as the fastest.
Which current processors keep the NVIDIA GeForce GTX 1070 from waiting, in a typical game at high settings. Faster than a group needs gains nothing you can see at that resolution, so the useful choice is the least powerful processor in the group you play at. Listed fastest first; each links to the full result for the pair.
Older processors keep up with the GTX 1070 at 1440p from the Core i7-2600K up. The least powerful that do:
Each processor and the GTX 1070 are compared at each resolution with the same model and the same reference data as the bottleneck calculator, which the Bottleneck app uses to judge the hardware it measures. It is an estimate for a typical game at high settings: strategy, simulation and large multiplayer games lean on the processor more, and so do lower settings and upscaling.
A GTX 1070 with the right processor can still fall short of these figures. Bottleneck checks the usual reasons a PC falls short of its parts, free: memory below its rated speed or in single channel, Resizable BAR and GPU scheduling left off, a monitor held at 60 Hz, heat. Then, while you play, it records which part set the pace in every frame.
The free version has no time limit and needs no account. Pro, $9 once, explains each problem and how to fix it, makes the common fixes in one click, and costs out the upgrade for your own PC. Compare the versions